Impact of chemical exposure on cancer mortality in a French cohort of uranium processing workers.

BACKGROUND: Nuclear workers may be exposed to a variety of chemical hazards, in addition to radiation. We examined the effect of chemical exposures on cancer mortality among French uranium processing workers at the AREVA NC Pierrelatte facility. METHODS: A cohort of 2,897 uranium processing workers employed for at least 6 months was followed from 1968 through 2006. Exposure to uranium and potentially carcinogenic chemicals was assessed with a plant-specific job-exposure matrix. Mortality hazard ratios (HRs) for cancers of the lung, lymphohematopoietic system, kidney and bladder, brain and central nervous system (BCNS), and prostate were estimated for each specific chemical exposure, with Cox regression models stratified for sex and calendar period and adjusted for socioeconomic status. Additional adjustments enabled us to examine the effect of co-exposure to uranium and other chemicals. RESULTS: Exposure to aromatic solvents was associated with increased risk of BCNS malignancies after adjustment for other chemicals (HR=6.53, 95% CI=1.14-37.41; n=6) and for other chemicals and uranium (HR=7.26, 95% CI=0.90-58.19) in the annual exposure status model. Selected groups of lymphohematopoietic cancers were found associated with solvent exposure. Inconclusive results were found regarding chromium (VI) exposure, since only 2 workers died from lung cancer among 109 exposed. CONCLUSION: Based on our pilot study, it seemed important to take into account chemical exposures in the analyses of cancer mortality among French uranium processing workers.

Assessment of efficacy of quercetin-5'-sulfonic acid sodium salt in the treatment of acute chromium poisoning: experimental studies.

Hexavalent chromium compounds exhibit higher toxicity than its trivalent compounds since chromium ions in the +6 oxidation state easily cross biological membranes. It has recently been proposed that substances reducing chromium ions from the +6 to the less toxic +3 oxidation state can be beneficial in management of acute chromium poisoning. In vitro studies also demonstrated quercetin-5 '-sulfonic acid sodium salt (NaQSA) to reduce chromium ions from the +6 to the +3 oxidation state. The aim of the study was to determine efficacy of NaQSA in treatment of acute poisoning with a hexavalent chromium compound. The experiment was carried out on male and female Wistar rats which were divided into 4 experimental (A,B,C,D) and control (K) groups. All animals received intragastrically a single CrO3 dose equal to its LD50. Thirty minutes after administration of CrO3, NaQSA was administered intragastrically at a dose of 50 mg/kg (group A) and 100 mg/kg (group B). In groups C and D, NaQSA was administered ip 2 h after administration of CrO3 and then twice a day for 4 days at doses of 50 mg/kg (group C) and 100 mg/kg (group D). Only intragastric administration of NaQSA at a dose of 100 mg/kg decreased mortality in acute poisoning with CrO3. In groups B and D, aminotransferase activity was statistically significantly dropping from day 7 of the experiment in comparison with the group K, which indicates lesser damage to the liver in animals treated with NaQSA. Bilirubin concentrations in groups B and D were also much lower than in the group K, but the difference between average bilirubin levels in these groups and the K was not statistically significant. The results of the study suggest the usefulness of NaQSA in the treatment of poisoning with hexavalent chromium compounds.

Death by tanning--a case of fatal basic chromium sulphate poisoning.

A woman ingested 400 ml of leather tanning solution containing 48 g of basic chromium sulphate (CrOHSO4). This substance forms hydrogen ions and trivalent chromium when it reacts with tissue proteins. The patient died of cardiogenic shock, complicated by pancreatitis and gut mucosal necrosis and haemorrhage. There are no reported cases of toxicity due to oral ingestion of trivalent chromium. Toxicity of hexavalent and trivalent chromium is discussed and suggestions made for management of future cases.